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There is a significant amount of waste generated which creates a huge environmental issue for humanity/earth and a tremendous number of varieties of resources of a different kind are needed globally. In this context, nanoscience technology has shown its potential ability to solve the above issues and provides realistic applications and devices. The beauty of nanotechnology is its multidisciplinary approach, in which green nanotechnology has been translated to focus on waste materials. Waste materials are generally generated from biogenic (rice husk, dead leaves, waste food, etc.) and non-biogenic (several types of plastics waste, lard oil, etc.) materials produced from municipal or industrial waste. Currently, a large number of efforts have been made to utilize the waste materials for the synthesis of 2D materials in a greener way. This green synthetic approach has two advantages 1) it reduces the cost of synthesis and 2) includes minimal use of hazardous chemicals. Biogenic wastes (contains biomolecules) contain several significant constituents such as co-enzymes, enzymes, proteins, terpenoids, etc. These constituents or biomolecules are known to play an energetic role in the formation of a different variety of 2D materials and hence control the protocols of green synthesis of 2D materials. This review focuses on the exploration of the current understanding of 2D-layered material synthesis methods using waste material produce from biogenic and non-biogenic waste. It also investigates the applications of various 2D-layered materials in perspective with synthesis from waste and future challenges along with their limitations to industrial-scale synthesis.

Green synthesis of nanoparticles (NPs) has gained great concern among researchers due to their unique properties, excellent applications and efficient route of synthesis. From the last decades, the number biologicals such as plants, fungus, bacteria, yeast, algae, and cyanobacteria and their products are using by various researchers for the synthesis of different NPs. However, the pillar of green chemistry keeps touching new heights to improve the performance. This review paper unveils almost recent cyanobacteria-assisted greener NP synthesis technique, characterization and application. The enormous potency of cyanobacteria in NP synthesis (silver, gold, copper, zinc, palladium, titanium, cadmium sulfide, and selenium) and significance of reducing enzymes were summarized. The extracellular and intracellular entity such as metabolites, enzyme, protein, pigments in cyanobacteria play a significant role in the conversion of metal ions to metal NPs with unique properties discussed briefly. The green synthesis of nanomaterials is valuable because of their cost-effective, nontoxic and eco-friendly prospects as well as the potential application metal NPs such as antibacterial, antifungal, anticancerous, catalytic, drug delivery, bioimaging, nanopesticide, nanofertilizer, sensing properties, etc. Therefore, in the present review, we have systematically discussed the mechanisms of synthesis and applications of cyanobacteria-assisted green synthesis of NPs.

The present study was aimed to synthesize silver nanoparticles (AgNPs)using the extract of oyster mushroom Pleurotuscitrinopileatus and its use in antibacterial testing. This green synthesis approach of silver NPs is very fast, simple, environmentally friendly and economical. The initial confirmation of silver NPs synthesis was observed with the alteration of the colour of the solution from colourless to wine red. The prepared nano-material was further characterized by UV-Visible spectrophotometer, and transmission electron microscopy (TEM). The TEM revealed particle size of synthesized AgNPsbetween the range of 11-13 nm. The bactericidal efficacy of silver NPstested against Escherichia coli confirmed the lowest 50 µg/L concentration of silver NPs bactericidal. Therefore based the observations of the study silver NPsat the level of its 50 µg/L can be used for the purposes of potential water disinfection, killing of bacteria, disinfection of medical equipments, wound washings, preservation of food stuffs and in hand sanitization.

Promotion of mushroom growth by means of biological agents replacing chemicals is an emerging and highly demanded issue in the sector of mushroom cropping. The present study was aimed to search for a novel bacterium potentially able to enhance mushroom growth and yield. A total of 2165 bacterial isolates purified from different samples were scrutinized through various growth-promoting attributes. As a consequence of rigorous screening, 26 isolates found exhibiting positive traits of mushroom growth promotion. Thereafter, in response to the cocultivation (fungus and bacteria), a potent bacterial strain was isolated capable to improve significantly the mycelial growth. In cocultivation the highest radial and linear growth rate was 7.6 and 8.1 mm/day on 10th and 11th days, respectively. The fruitbody yields and biological efficiency (BE) of the inoculated sets were 28% and 58% higher than the uninoculated control sets. The bacterium was molecularly identified based on 16S ribosomal RNA sequencing and confirmed as Glutamicibacter arilaitensis MRC119. Therefore, the bioinoculant of the current bacterium can be potentially useful as an ecofriendly substitute stimulating the production of mushroom fruit bodies with improved BE.

Biodecolorization potentials of three distinct white-rot fungi including Pleurotus florida (PF), Pleurotus eryngii (PE) and Pleurotus sajor-caju (PS) were assessed both in liquid and on solid media supplemented with carpet industry dye brilliant green. All three fungi produced laccase and peroxidase enzymes. The decreasing order of laccase production was achieved as 388 > 334 > 301 IU/mL in cultures of PF > PE > PS during 15th, 20th and 17th days, respectively, while, decreasing order of peroxidase production was as 72 > 64 > 55 IU/mL in PF > PE > PS on 15th day of PF, PS cultures and on 20th day of PE, respectively. All tested fungi very efficiently degraded different levels (2, 4, 6 and 8%; w/v) of highly complex synthetic brilliant green dye to colorless. However, PF was found to be best amongst the three species tested on solid and in liquid media. In comparison to higher concentrations, lower concentrations of dye were rapidly biodecolorized by all fungal strains. The order of highest biodecolorization potentialities was recorded as 99 > 91 > 83% by PF > PE > PS, respectively with 2% (w/v) of dye under submerged conditions. While, experimental sets with 4% (w/v) dye were found as the second most rapidly biodecolorized sets, that resulted in 90 > 78 > 70% by PF > PE > PS strains respectively. Based on the findings of biodecolorization potentialities PF was most efficient fungus as compared with other fungi by degrading 99% of the 2% (w/v) dye. Therefore, PF can be subjected in the eco-friendly and cost-effective industrial effluent cleanup processes for the environmental sustainability.

The versatile fungal genus Trichoderma is the most culturable fungus and is industrially exploited at a large scale for the production of several multipurpose enzymes such as pectinase, cellulase, xylanase, chitinase, lipase, protease, amylase, manganese peroxidase, and laccase. This excellent characteristic of synthesizing such a multitude of enzymes ranks this fungus as a magnificent industrial cell factory of enzymes. The present chapter covers the up-to-date information regarding the experimental production of multiple multitask enzymes under different fermentation conditions. The chapter presents a detailed account of potential application of the aforementioned enzymes for different human uses as Trichoderma possesses a highly versatile synthetic machinery producing enzymes for numerous applications. As is well known, these enzymes are widely used in different areas such as production of biofuels, textiles, pulp and paper, food, animal feed, biorefineries, biocontrol, medicine, leather, growth promoters, detergents, fruit juice clarification, antimicrobial purposes, and detoxification of pollutants as well as in waste management. This chapter also explains the biotechnological strategy of gene cloning. In this reference, the important studies have been compiled wherein cloning of the genes responsible for the synthesis of several enzymes has been achieved in bacterial and yeast cells as potent hosts for their successful expression.

The muscarinic acetylcholine receptors (mAChRs) are receptors that produce the GPCR complex in the membrane of specific neurons and other cells. It performs a key role at the end of the receptor stimulated by the neurotransmitter. Ach liberates from postganglionic neurons in a parasympathetic region of ANS. The mAChRs constitute a family of five interrelated GPCRs that come under the category of α branch of GPCRs’ Class A. The five different subtypes of the mAChR family are designated as M1–M5. M1, M3 and M5 subtype receptors exhibit to pair through the Gq/11 family of G proteins, but the M2 and M4 subtype receptors particularly indicate through Gi/o family of G protein. The mAChRs play multifunctional peripheral and central roles in human physiology including regulation of muscle contraction, heartbeat, lung, secretion by gland and other functions of the CNS.

Recent interests with copper nanoparticles (Cu-NPs) has arisen because of its low cost and antibacterial properties, as it may be one of the very important alternatives to silver NPs. Pulsed laser ablation of a solid target (copper) in liquid media is used to synthesize colloidal oxide copper (Cu2O and CuO NPs) NPs. These oxides of copper NPs were synthesized using Nd:YAG laser energy to maintain a 40 mJ/pulse wavelength at 1064 nm. During the synthesis of colloidal NPs only two conditions were opted, employing double distilled water (without PEG) and 10% preparation of PEG. Both NPs were prepared under the similar parameters such as optimized instrument settings, laser energy and time of laser exposure (1 h ablation). Further, these copper oxide NPs were characterized by advance technologies including UV–visible, X-ray diffraction, transmission electron microscopy and attenuated total reflection Fourier transform infrared spectroscopy techniques. The significant antibacterial properties of synthesized materials were also observed. The cuprous oxide NPs, showed remarkable antibacterial effect conducted using disc diffusion techniques. The minimum inhibitory concentration and minimum bactericidal concentration of synthesized Cu2O NPs were recorded as 120 and 140 μg/L respectively against Staphylococcus aureus used as positive control. Therefore, based on the findings of present study Cu2O NPs can be exploited as stable antimicrobial agents for multipurpose uses.

Aim of the present study was to evaluate the efficiency of fungal co-culture for the decolorization of synthetic brilliant green carpet industry dye. For this purpose two lignocellulolytic fungi Pleurotus florida (PF) and Rhizoctonia solani (RS) were employed. The study includes determination of enzyme profiles (laccase and peroxidase), dye decolorization efficiency of co-culture and crude enzyme extracts. Both fungi produced laccase and Mn peroxidase and successfully decolorized solutions of different concentrations (2.0, 4.0, 6.0, & 8.0(w/v) of dye. The co-culture resulted highest 98.54% dye decolorization at 2% (w/v) of dye as compared to monocultures (82.12% with PF and 68.89% with RS) during 12 days of submerged fermentation. The lower levels of dyes were rapidly decolorized, while higher levels in slow order as 87.67% decolorization of 8% dye. The promising achievement of the study was remarkable decolorizing efficiency of co-culture over monocultures. The direct treatment of the mono and co-culture enzyme extracts to dye also influenced remarkable. The highest enzymatic decolorization was through combined (PF and RS) extracts, while lesser by monoculture extracts. Based on the observations and potentiality of co-culture technology; further it can be exploited for the bioremediation of areas contaminated with hazardous environmental pollutants including textile and other industry effluents.

Oyster mushroom (Pleurotus spp.) is one of the very attractive crops successfully cultivated in most developing countries due to its easy cultivation technology. The most amazing point of mushroom cultivation technology is its landless agriculture on useless lignocellulosic agricultural wastes. The oyster mushrooms have potentials to utilize various kinds of waste materials as substrate than any other mushrooms and in consequence convert them into valuable vegetable food at par with non-vegetarian food in terms of nutritional attributes. Since these natural lignocelluloses contain limits of their nutrient constituents, require supplementations in the form of chemical and biological supplements. Addition of the supplements with basal substrate has been as common practice to enhance the yield, nutritional and medicinal values. The present manuscript comprised the detailed information in context of oyster mushroom cultivation, used multiple basal substrates and supplements (additives) as reported in past researches. Therefore, the technology of mushroom agriculture enables us to acquire substrate materials at very low cost or even for free to get biotechnological foods and further led to conserve our environment through efficient bioconversion of wastes with sustainable food security.

Bioactive compounds are very diverse metabolites produced by almost all types of living creatures including plants, animals, algae, fungi, and bacteria. These compounds include metabolites such as antibiotics toxins, alkaloids, food grade ingredients, growth factors, and phenolics. They have extremely important biological activities, such as being antioxidants and antimicrobials, having antiinflammatory, antifouling, anticancer (antitumor), and antiallergic properties, and acting as enzyme inhibitors. The plant raw materials containing such compounds have been used for the treatment of human and animal diseases since the ancient times. In recent years these compounds have attracted a wide community of researchers, physcians, toxicologists, and nutritionists, in order to extract these compounds from agroindustrial sources for their potential applications in the food, chemical, and medical industries. The purified bioactive ingredients of the raw materials may provide more specific and prompt cures of various human disorders. Therefore there is a desire for the discovery of novel bioactive compounds synthesized as part of secondary metabolism in a number of organisms. Microorganisms are ubiquitous, can be easily cultivated in the laboratory, and serve as sources of novel bioactive compounds in a sustainable manner. Metabolites have been used neutraceutically and pharmaceutically for the treatment of various diseases. Therefore more exploration of the bioactive compounds from diverse sources will lead to the development of new technologies in the search of novel compounds. The present chapter discusses important examples of the bioactive compounds extracted from different sources including plants, invertebrates, bacteria, fungi, and algae and their biological applications.

Lignocelluloses are highly composite polymeric material structurally and integrally composed with several repeating units of cellulose, hemicellulose, and lignin. These are abundant in nature particularly in wood, grass, agricultural, and forestry waste and have a potential of bioconversion into valuable metabolites. Sometimes, the vast amount of these lignocelluloses create big environmental issues when either thrown or burnt negligently. Thus, rather than throwing them uselessly in surrounding environment, they may be microbially processed for bioconversion into useful products. A broad group of microorganisms including fungi, bacteria, and algae have versatile skill to degrade lignocelluloses by yielding a variety of valuable products. The fungi are known to be most potent because of their excellent enzymatic system and ability to degrade lignocellulosic materials. The synergistic action of multiple enzymes such as laccase, peroxidase, endoxylanase, endoglucanase, exoglucanase, β-xylosidase, and β-glucosidases converts lignocellulosic complexes into monomer forms to avail nutrients towards fungal mycelia. These enzymes have distinct catalytic functions that attacks on the complex structure of lignocelluloses and consequently yields the simpler metabolites. In response, a variety of fungal species produce a cluster of metabolic products beneficial in human appliances. The present chapter summarizes the clear explanations focusing on the basic mechanism of lignocellulosic conversion into their monomeric forms. The present chapter mainly focus on various aspect of efficient biodegradation and bioconversion of lignocelluloses with a sustainable approach to proceed lignocellulose material into value added forms. The important multi events during the mycodegradation of lignocelluloses including hemicellulolysis, cellulolysis, and ligninolysis are elaborated in detail in separate sections.

Polyaromatic hydrocarbons (PAHs) are a group of more than hundred highly toxic, recalcitrant, and carcinogenic organic compounds, generated after incomplete combustion of organics, and persist in the environment as very noxious pollutants. Generally, several anthropogenic activities often pollute the upper fertile and rhizosphere soil of earth that exerts multiple harmful influences on the ecosystems. The severe contaminations from PAHs cause ill health of soil by the damage of plant, animals, and microorganisms, which may result in imbalance in the ecosystem. Though various physical and chemical methods have been attempted, they were found inappropriate, non-economical, and non-ecofriendly. The rhizoremediation presents itself as a potential approach for the remediation of soil from the PAHs using plant and rhizosphere microbes. The synergistic interaction of plant and existing rhizosphere bacteria has a wonderful role in bioremediation of PAHs, which constitutes rhizoremediation as an excellent and very attractive green technology. Under the integrated rhizoremediation approach of PAHs, plant roots on one side secrete organic exudates, while on the other side, bacteria contribute various enzymes to degrade recalcitrant PAHs into non-toxic forms. Thus, this eco-friendly technology establishes an approach, which not only limits to PAHs but also has a broad spectrum of bioremediation for various other recalcitrant organic pollutants such as chlorinated phenyls, explosives, insecticides, fungicides, etc. In consequence, practical implementation of rhizoremediation at ground level for decontamination of highly polluted sites needs to be promoted. The present chapter emphasizes detailed account on rhizoremediation of PAHs using an integrated approach of plant and microorganisms.

Important carbohydrate polymers in form of lignocelluloses are biocatalytically decomposed into their basic fermentable sugars with the action of cellulolytic enzymes. The major enzymes include are β-1, 4-Xylanase and β-1, 4-Endoglucanase degrading xylans and celluloses respectively. The microorganisms containing specific structural genes in their genomes superfluously produce these two enzymes and their respective isozymes. The clusters of genes synthesizing both enzymes are expressed under very optimized conditions which varies from genus to species level. The inducer and suppressor compounds also influence the expression of genes responsible for β-1, 4-Xylanase and β-1, 4-Endoglucanase production. The present chapter is comprised of degradation cellulose and xylan into simple sugars, detailed account of both enzymes, clusters of genes and their expression and regulatory expression mechanisms. Advanced knowledge of gene expression in relation to specific host may strengthen the strategy of novel strain development using recombinant technology and genetic engineering.

Simultaneous increasing in household and agricultural waste is directly proportional to rising population and development of society. Similarly high demand of sustainable energy and materials requires improvements in renewable energy production technology to meet the global demands. From the last few decades, scientists are consistently attempting for improved conversion of voluminous complex lignocellulosic biomass into simpler C5 and C6 sugars, which can be further converted into different valuable products using biochemical and physicochemical routes. However, complex properties of lignocelluloses, their recalcitrant nature to degradation and non-economical availability of enzymes can promote towards transformation using engineered nanoparticles (NPs) as a nanocarrier. The nanosupport immobilized lignolytic enzymes have emerged as an eco-friendly sustainable technology to resolve above issues. This chapter deals the role of different NPs immobilized enzymes in improvement of enzyme stability, activity, reusability, recovery, and lignocellulose conversion ability in different fuels, materials, and value-added chemicals. These practices may reduce fuel cost, adverse effect of fossil fuel, and global pollutions.

Efficient bioconversion of complex lignocelluloses to their simpler units of monosaccharides using hydrolytic enzymes from microorganisms is an attractive biochemical engineering process. The huge biodiversity of Penicillium makes it a promising microbial bioresource for saccharifying lignocellulosic feedstocks into fermentable sugars. This chapter discusses the major constituents of lignocellulosic feedstocks and the lignocellulolytic enzymes used in the lignocellulose saccharification that are produced by different member strains of Penicillium genus. Penicillium contains very strong machinery producing ligno-cellullolytic enzymes, which enables this group of fungus to conduct multiple applications related to efficient bioconversion. Because of its remarkable characteristics this fungus is now the choice of biotechnologists, and is being employed in multiple industrial processes and research projects.

Synthesis of nanoparticles using the filamentous fungus Penicillium is a promising ecofriendly approach with a multitude of applications in the medical sciences. This chapter covers the prospects of structural and morphological variations, synthesis, and multiple applications of nanoparticles in the field of pharmaceutics. The chapter also covers the general characteristics, size-based classification, and synthesis of Penicillium and pharmaceutical uses of nanoparticles. Several studies using Penicillium nanoparticles of different metals such as gold (Au), silver (Ag), and copper (Cu) are summarized as well. The protocols and mechanisms for both the extracellular and intracellular synthesis of Pencillium-mediated nanoparticles are illustrated in multistep flowcharts. Biologically synthesized nanoparticles have great significance in different fields of science especially in pharmaceutical science as discussed in this chapter.

Oyster mushroomPleurotus floridawas cultivated on different combinations of wheat straw (WS) as basal substrate and oyster shell powder (OSP) supplement. The OSP supplementation considerably responded to different cultivation phases. The mycelium grew fast and showed rapid growth rate (8.91 mmd−1) in WS + OSP (97 + 3) combination while WS + OSP (92 + 8) showed maximum laccase (3.133 U/g) and Mn peroxidase (MnP) activities (0.091 U/g). The climax level of laccase (5.433 U/g) and MnP (0.097 U/g) was recorded during fruit body initiation in WS + OSP (97 + 3) and WS + OSP (98 + 2) combinations, respectively. The WS + OSP (97 + 3) combination represented the best condition for mushroom cultivation and produced the highest biological efficiency (147%). In addition, protein and lipid contents in fruit bodies were slightly improved in response to OSP. The carbohydrate was significantly increased by raising concentration of OSP. The highest values of protein, carbohydrate, and lipid noted were 31.3 μg/g, 0.0639 (g/g), and 0.373 (g/g) correspondingly. Conclusively it was evident that lower concentrations of OSP acted positively and relatively to higher concentrations and improved nutritional content which may suitably be used to enhance both yield and nutritional values of mushroom.

Irrational and rapid global human societal development has culminated to a condition of environmental deterioration. Accidental leakage and deliberate use of organic and inorganic chemicals have contaminated the environment up to the level of ecosystem. Advancements have been made in the field of research on bioremediation of the hazardous contaminants especially in last three decades. Microbial bioremediation has been the most understood biotechnological process of environmental restoration. Bacteria and fungi because of their inherent ability to adapt and grow in extreme environments have been employed for either removal or degradation of the chemical contaminants. Researchers all over the world are getting breakthroughs in finding new bacterial strains having plasmid linked degradation/reduction ability. Molecular biology and genetic engineering helped in crafting the microbes for the desired results on environment. Despite having favorable conditions, microbial remediation largely depends on environmental factors and on the basic biological characters of microbes, especially bacteria being Gram-positive or Gram-negative. Metagenomic studies revealed the importance of microbial ecology as microbes work well in community, i.e., consortia. This review along with several other studies suggests the need of precision during microbial community identification, substrate specificity and the designing of microbes.

Two commercial oyster mushroom species, Pleurotus florida PF05 (PF) and Pleurotus sajor-caju PS08 (PS), were cultivated on wheat straw (WS), corn cob (CC) and combination of both (CC + WS) as basal substrates. These substrates were deliberately supplemented with 5, 10, 20 and 40% of dairy spent wash (DSW) as additive. The influence of DSW on cultivation phases of both mushrooms’ lifecycle and other parameters such as mycelial growth rate, ergosterol production, mycelial run, pin head formation, yield, biological efficiency (BE) and protein content in fruitbodies was evaluated. Different DSW concentrations significantly (P flush-II > flush-III with considerable differences. These results suggest the use of DSW at low levels for increasing fruit body yield and BE of Pleurotus mushrooms.

The presence of arsenic (As) in water is of great public concern. Arsenic exists in three common valence states viz., As(0) metalloid arsenic, As(III) (arsenite) and As(V) (arsenate). Arsenite [As(III)] is the most toxic form among arsenicals which, predominates in anaerobic conditions, generally in flooded soils and in the water with high BOD. Experiments were conducted to investigate the effect of As(III) on the mycorrhization in vetiver (Vetiveria zizanioides (L.) Nash) grass in hydroponics. Studies showed significant alteration in the mycorrhizal colonization in the roots of vetiver exposed to higher concentrations of As(III) starting from 1.0, 2.0, 3.0, 4.0 to 5.0 mg/L prepared in 5% Hoagland nutrient solution without addition of phosphate ions. Considerable reduction in the mycorrhizal intensity (M) was observed in all the treatment sets as compared to the control suggesting a negative impact of the As(III) on the mycorrhizal association. Simultaneously, the study also showed that, As(III) is toxic to the vetiver plants having mycorrhizal association however plants with non-mycorrhizal (cleansed) roots were found to be able to survive for a longer period exposed to As(III).

The cultivation of white rot edible fungus Pleurotus florida was performed in polybags. The corn cob was employed as basal substrate while eight different additives such as urea, ammonium sulphate, gram flour, soybean meal, ground nut cake and molasses were used with corn cob. Three different levels of variable combinations with corn cob were evaluated in response to different parameters of mushroom viz., mycelial growth, spawn running, primordial initiation, fruit body yield and its biological efficiency. Each additive at different combinations showed variable impact on the different stages of mushroom life cycle. The primordial initiation was observed for the first time during 20.2–35.1 days. The biological efficiencies in every supplemented set were increased over un-supplemented control set. Increasing the level of additives, the biological efficiency was negatively affected at higher levels. The cotton seed cake was found the best supplement producing 93.75% biological efficiency while soybean meal was the second best additive producing 93.00% yield. The highest growth rate, rapid mycelia run, early primordial initiation, highest yield and biological efficiency were recorded in the combination of corn cob and cotton seed cake at 2% (98 + 2) level.

The ability of seven hyperaccumulator macrophytes which grow naturally in the heavy metal contaminated channels of three different industries (Hindustan Aeronautical Ltd., Eveready Ltd., and Scooter India Ltd.) to accumulate heavy metals was recorded. All these industries use electroplating processes in their manufacturing and are located in the inner area of Lucknow City, U.P., India. Of the three industries monitored, effluent released from Eveready Ltd. contained the highest concentration of heavy metals. In general, accumulations of heavy metals depend upon the plant species and the metal concentration in the media. All plant samples showed heterogeneous metal accumulations, except for Fe or Cd. It was observed that some plant species accumulated high level of metals, e. g., Eichhornnia crassipes for Fe (4052.44 μg/g), Mn (788.42 μg/g), and Cu (315.50 μg/g), and Spirodela polyrhiza for Cd (12.75 μg/g), Pb (20.25 μg/g), and Cr (128.27 μg/g), even when the metal concentrations were not high in the effluent. In summary, these two plants were found to be the best accumulators at each contaminated site. The results will be helpful in the selection of plant species which can be used as bioaccumulators or bioindicators.

Heavy metal contamination of the rivers is a world wide environmental problem and its removal is a great challenge. Kanpur and Unnao two closely located districts of Uttar Pradesh India are known for their leather industries. The tanneries release their treated effluent in the near by water ways containing Cr metal that eventually merges with the river Ganges. Untreated tannery effluent contains 2.673 ± 0.32 to 3.268 ± 0.73 mg l–1 Cr. Microbes were isolated, keeping the natural selection in the view, from the tannery effluent since microbes present in the effluent exposed to the various types of stresses and metal stress is one of them. Investigations include the exposure of higher concentrations of Cr(VI) 1.0 to 4.0 mg l–1 to the bacteria (presumably the Pseudomonas spp.) predominant on the agar plate. The short termed study (72 h) of biosorption showed significant reduction of metal in the media especially in the higher concentrations with a value from 1.0 ± 0.02, 2.0 ± 0.01, 3.0 ± 0, and 4.0 ± 0.09 at zero h to 0.873 ± 0.55, 1.840 ± 1.31, 2.780 ± 0.03 and 3.502 ± 0.68 at 72 h respectively. The biosorption of metal show in the present study that the naturally occurring microbes have enough potential to mitigate the excessive contamination of their surroundings and can be used to reduce the metal concentrations in aqueous solutions in a specific time frame. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Extensive research is being conducted world- wide to find alternative and efficient systems to lessen the impacts of climate change and reduce environmental pol- lution. The genus Phragmites has proven ability to mitigate the environmental pollution of its surroundings. Common reed (Phragmites australis (Cav.) Trin. Ex. Steudel), a graminaceous plant of cosmopolitan nature, has been extensively studied especially for the mitigation of envi- ronmental contamination. The capability of common reed to grow well at extreme environmental conditions such as elevated CO2 and high temperature is conferred by several factors such as change of carbon trapping mechanism (from C3 to C4 and vice versa), microbial association and biochemical adaptations. P. australis has been a most preferred unique plant system, especially in ecological engineering for improving the quality of wastewater. This paper reviews the current state of knowledge regarding the suitability of Phragmites australis for environmental remediation and summarizes recent advancements in our understanding of this grass.